The invention relates to an antenna device for transmitting and receiving RF-signals from and to a radio communication device, comprising: an extendable elongated flexible antenna element having first and second ends, whereof the first end has a first end portion; a casing through which said antenna element is slidable between an extended position, where the first end portion is mechanically locked in the casing, and a retracted position; and, a first opening in a first end of the casing through which the first end portion of said antenna element can be introduced, and a second opening in a second end of the casing through which the antenna element is slidable. Specifically, it relates to an antenna device for a mobile radio communication device, e.g. a hand-portable telephone.
Such an antenna device is previously known from WO 94/28593, wherein an antenna rod at its lower region is provided with a rigid stopper element which, in the extended position, cooperates with a resilient sleeve member so as to obtain a locking force between these parts.
The prior art device is well functioning, however, relatively space-demanding in the axial direction, since the sleeve construction necessarily have relatively large axial dimensions and because the end portion of the stopper element appearing on the outside of the sleeve in the extended position. Further, a device based on the prior art solution includes several separate details such as a sleeve, a spring ring for the sleeve, a screw portion and a stopper element, resulting in correspondingly high costs for manufacture, on the one hand of the separate elements and on the other hand for assembly of the elements. The use of several elements also results in accumulated and more widely spread tolerances. Further, the use of springs and separate details including springs put hard requirements on the design and the materials, in order to achieve long durability.